In Fig.8.1, it is given that BDEF and FDCE are parallelograms. Can you say that BD = CD? Why or why not?
∵ BDEF is a parallelogram
∴ BD = FE and BD ∥ FE …(1)
Similarly,
∵ FDCE is a parallelogram
∴ CD = FE and CD ∥ FE …(2)
From (1) and (2),
BD = CD and BD ∥ CD
Hence, BD = CD.
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